Low-bandwidth Net Radio 143
An anonymous reader writes "Slate has an article about Internet radio stations that use the aacPlus codec from XM satellite radio instead of MP3. Some of the ones they link to sound pretty good even at 24 kbps."
What about other codecs... (Score:3, Interesting)
Re:What about other codecs... (Score:5, Insightful)
So if your MP3s sound like crap
- up the bitrate to something reasonable
- Get a good source to encode from
- change the encoder [lame -q 0 is great]
Tom
Re:What about other codecs... (Score:2)
Well, strictly speaking any subband coder uses psychoacoustical modelling since it depends on frequency masking, but IIRC layer 2 and layer 3 both use subband coding.
Re:What about other codecs... (Score:2)
Re:What about other codecs... (Score:1, Funny)
Here's how 24kbit/s MP3 sounds (Lessig audiobook) (Score:4, Interesting)
Listen to Ch.1 by Doug Kaye and/or Ch.13 by George Sessum, as those files were properly recorded (some of the others were first-time recordings, and they didn't get their levels right).
Re:Here's how 24kbit/s MP3 sounds (Lessig audioboo (Score:2)
I've never heard true mono. Is it better than that fake mono I've heard people rave about?
Re:Here's how 24kbit/s MP3 sounds (Lessig audioboo (Score:3, Informative)
Some people wind up saving mono files that duplicate the audio on both right and left channels, rather than save it with a single mono channel.
You wind up with a file that's twice as big, with no benefit.
Re:What about other codecs... (Score:5, Interesting)
Anyhow, the MPEG-2 AAC and MPEG-4 AAC are basically identical, except for the addition of some coding tools designed for low bitrate encoding, like internet radio.
There are some profiles for AAC encoding, which are (in decreasing quality) Main, Low Complexity (which we see in FAAC and Apple's), Low Delay, and the newest is High Efficiency which is low bitrate. There's also a scalable profile thrown in for good measure. I presume AACplus is actually AAC-HE. The technology they're using is from MP3plus we've seen quite some time ago but never takes off. So rest assured that you're not missing anything if you got your collection coded in AAC-LC.
Also, the previous poster is correct. The psychoacoustics are not defined in the standard. Hell, even the encoder is not actually defined. They only define the decoder and the stream format to ensure interoperability. But yes, obviously MDCT sizes are clearly defined otherwise you can't reverse transform the coefficients. But if you so choose you can ignore their specification on transient handling and your stream will decode correctly, although with crap quality.
Re:What about other codecs... (Score:2)
>technology they're using is from MP3plus we've seen
>quite some time ago but never takes off. So rest
>assured that you're not missing anything if you got
>your collection coded in AAC-LC.
Well, HE-AAC got accepted into pretty much every broadcasting standard there is. I don't think you can "take off" more than that. Customers generally aren't aware of it, but that doesn't matter - companies sell solutions (iPod) rather than formats (AAC) anyway.
BTW. Y
Re:What about other codecs... (Score:1)
Anyway it's all for the best. We get better quality music that's actually decent using dial up with a format no one company controls so we can use our player of choice. I noticed the steady decline of realaudio content that requires a pain in the ass player to listen to.
Re:What about other codecs... (Score:2)
Probably because it's a fully closed standard (unlike HE-AAC, MP3, Vorbis, etc...)
HE AAC==AAC+ (Score:3, Informative)
Next up is AAC PS, for parametric stereo, which applies the SBR techniques to synthesizing stereo. Gives another big leap yet for music listening - 24 Kbps is good enough for people who can live with MP3 @ 160 or so.
Just a random thought here, (Score:5, Funny)
But hey, what do I know?
Re:Just a random thought here, (Score:3, Interesting)
Re:Just a random thought here, (Score:1)
Re:Just a random thought here, (Score:4, Informative)
It can be compared to any other radio broadcast; just because you're listening to 99.9 RIAA-0wn5-j00 FM doesn't mean other people have a weaker signal or diminished sound quality.
-Z
Re:Just a random thought here, (Score:3, Informative)
they wont have a diminished sound quality (for the most part, if its all on the edge of the range they might). but they most definately will always have a weaker signal in the immediate area. this is because your antenna itself distorts the field around it when it attracts the singal, and a small amount of energy is used in the reproduction of the sound wave when the receiver
Re:Just a random thought here, (Score:1, Informative)
Re:Just a random thought here, (Score:2)
Re:Just a random thought here, (Score:2)
A receiver tuned into a radio broadcast may affect the signal as it passes it, but it won't affect the transmitter in any way.
low bitstreams not so bad (Score:2, Interesting)
Ogg streaming seems pretty good (Score:5, Interesting)
http://www.virginradio.co.uk/thestation/listen/og
Re:Ogg streaming seems pretty good (Score:2, Funny)
Re:Ogg streaming seems pretty good (Score:2)
Re:Ogg streaming seems pretty good (Score:2)
But after listening to a 24kbit stream of AACplus, I have come to the conclusion that Vorbis just got it's ass handed to it at low bitrates. Seriously, 44khz stereo at 24kbit and it sounds great.
I'm trying to find an AACplus encoder somewhere to do some side-by-side comparisons.
Re:Ogg streaming seems pretty good (Score:1)
It's the weeken
Re:Ogg streaming seems pretty good (Score:1)
James (who works at Virgin Radio)
Avoiding the 'L' word.... (Score:3, Interesting)
I like how they avoided using th 'L' word in their report.
Re:Avoiding the 'L' word.... (Score:3, Interesting)
Oh, that's right. Linux is the only acceptible non Windows/MacOS operating system.
Re:Avoiding the 'L' word.... (Score:1)
Re:Avoiding the 'L' word.... (Score:1, Insightful)
Besides, why make MacOS a special case? The cumuled marketshare of all Linux distros is well over the Apple one.
Please, don't try to hide the bias when it's obvious.
Ah, the joy of posting anonymous.
Re:Avoiding the 'L' word.... (Score:2)
Disclaimer: I an not trying validate the ignoring of Linux. I use quite often myself.
I think it's not as much a matter of how many overall users there are as it is who they are. While there are lots of Linux installs out there, how many are actually desktop systems rather than servers? And of those, how many are someone's primary system? Etc.
In terms of mainstream users, Linux still seem
Re:Avoiding the 'L' word.... (Score:2)
XM @ 40kbps per music channel, quality still OK (Score:3, Interesting)
Speaking of XM, it seemd to be feast or famine- either they're playing stuff I like on several channels at once, or I flip around for an entire hourlong drive withouth finding anything - the other main reason why I canceled.
Re:XM @ 40kbps per music channel, quality still OK (Score:1, Informative)
I've reencoded files in OGG, WMA at 64kbs, and it's fairly equivalent
You're reencoding from XM and trying to compare quality? The XM codec has already thrown away lots of information, transcoding to another format is only going to throw away more, it's certainly not going to magically get the information back somehow.
It's like chopping an apple in half, and trying to determine whether you can chop one of the halves in a way that gets you more than half an apple. Impossible by definition.
The Interesting Bit is in the Last Paragraph (Score:5, Insightful)
Then you get to this bit:
It seems crazy until you try it, but Mostly Classical proves that aacPlus can sound great at 24 kpbs. At 48 kbps, it's almost as crisp as a CD. At 128 kbps, it can deliver 5.1 channel surround sound.
Using the compression to deliver multichannel surround sound is pretty cool. In 5, 10 years, we'll probably have a really flash standard for home audio, and it's nice to know that some folks are thinking ahead to make sure we'll be able to get it streaming on our DSL lines.
Re:The Interesting Bit is in the Last Paragraph (Score:3, Interesting)
By the way, if you know of an ogg encoder that will support 5.1 let me know, I don't want to develop it myself, I don't have time.
Re:The Interesting Bit is in the Last Paragraph (Score:1)
Re:The Interesting Bit is in the Last Paragraph (Score:2)
I wish open source advocates would quit saying stuff to the effect of "write it yourself". Even though it probably isn't meant to be insulting, not a whole lot of people can actually do it and do a good job of it. Do a bad job and it's probably easier for contributor to rewrite it from scratch than it is to advance the project.
Re:The Interesting Bit is in the Last Paragraph (Score:1, Insightful)
At least this one was not as insulting as some I've read. If Linus says, "I'd really like XYZ," would these people act the same way? People have areas of expertise. Even an ace programmer can't program in ever field.
Re:The Interesting Bit is in the Last Paragraph (Score:2)
I may do it just to see pictures of the parade.
Re:The Interesting Bit is in the Last Paragraph (Score:2)
What's the problem? oggenc will have no problem encoding from a 6-channel wav file.
The problem right now is that the ogg encoder doesn't do the differential-encoding thing, saving only the differences between each of the channels, making the stream much smaller. It's capable of doing it, but the code hasn't been written yet.
As a matter of fact, Ogg/Vorbis in general hasn't really been updated since it's 1.0 release years ago. Someb
Re:The Interesting Bit is in the Last Paragraph (Score:2)
So? That doesn't mean that server load and server bandwidth isn't a factor preventing people from getting into the game, reducing these two means more people can use a server.
Re:The Interesting Bit is in the Last Paragraph (Score:3, Interesting)
Re:The Interesting Bit is in the Last Paragraph (Score:1, Interesting)
It's mentionned here at the end of the page:
http://www.xiph.org/ogg/vorbis/faq.html
something about the coupling
http://www.xiph.org/ogg/vorbis/doc/stereo.html
You can encode to multichannel from raw audio input it seems/I think (haven't tried it):
The program "oggenc" has an option "-C" where you can define the number of channels. This is a command-line-tool. It seems it was
Motor vehicles need mobile connections (Score:2)
Truth is, everyone (at least in the west and industrialized Asia) has or will get broadband
Wired broadband and fixed wireless broadband do not count. It has to be a mobile connection, or it won't stand a chance of replacing Clear Channel's FM and XM programming in motor vehicles. Currently, affordable mobile connections are rather low-throughput, so they'll need a decent codec.
Re:The Interesting Bit is in the Last Paragraph (Score:1)
Re:The Interesting Bit is in the Last Paragraph (Score:2)
Re:The Interesting Bit is in the Last Paragraph (Score:2)
Low bit rates works well with speech. (Score:4, Interesting)
I think because we're so used to talking over landline telephones with its relatively poor sound quality, Windows Media and Real audio streams transmitted at 16 kilobits per second and the audio stream mentioned in the article sounds reasonably well for mostly-speech programming.
Re:Low bit rates works well with speech. (Score:2)
I'm no scientist, I just like to observe things and try to come up with a reason why they happen.
Re:Low bit rates works well with speech. (Score:1)
The exact point you're making is called the fields of psychoacoustics,
Re:Low bit rates works well with speech. (Score:2)
Allow me to suggest this as your sig file.
Re:Low bit rates works well with speech. (Score:2, Insightful)
Your ordinary GSM cell phone works at 16 kbps, off the top of my head, I don't exactly remember. Your landline works at roughly the same bitrate. The reason why we don't see an increase in speech quality is due to existing equipment that'll be t
Re:Low bit rates works well with speech. (Score:2)
Re:Low bit rates works well with speech. (Score:1)
The overkill part I'm referring to is the audio specific psychoacoustic processing which requires even heavier calculation than linear prediction since it has to calculate many variables. But as soon as it leaves that stage, everything else is quite simple by comparison.
But then again, when working at very low bitrates and the application is speech specific, audio coders simply can't compete with speech co
Re:Low bit rates works well with speech. (Score:1)
i agree with the fact that its nonsense that people commonly refer to ogg vorbis as simply 'ogg' where as there are many projects under the ogg umbrella: vorbis, flac, speex, theora; all of which can have ogg appended before them, but i can understand why 'ogg' has come to mean vorbis:
platform irony (Score:3, Interesting)
OK, so Winamp isn't installed by default, but is is becoming the player of choice for the IT cogniscenti in place of WMP, whereas other Mac players are still the curiosity compared to iTunes.
Re:platform irony (Score:2)
OK, so Winamp isn't installed by default, but is is becoming the player of choice for the IT cogniscenti in place of WMP, whereas other Mac players are still the curiosity compared to iTunes.
Last I heard, WinAmp was a discontinued product. That's irony for you.
The article mentions that VLC can play AAC+. I bet VLC is installed on most desktop Macs used by the "IT cogniscenti", alongside iTunes. Furthermore, iTunes supports audio format plug-ins (I don't know whether there exists an AAC+ plug-in.)
Re:platform irony (Score:2)
Re:platform irony (Score:4, Insightful)
Hm. First off, I wouldn't say that Winamp is becoming anything - it already is, and has been for a while. People, and not only "IT cogniscenti" (aka geeks), have been using Winamp in the days when WMP wasn't a generally known acronym. To me, Winamp was the player of the period when MP3 was still new (remember oth.net and AudioGalaxy?). I kind of doubt the number of users is still increasing, in fact I imagine that if anything, the number is decreasing.
I might be wrong, though - so, what is the choice among the geeks these days? Do you all still use Winamp? Personally, I've been using Foobar [foobar2000.org] for a long time now, mostly because of it's small footprint, straightforward interface and out-of-the-box global hotkeys. Because I'm so happy with it, I really haven't even looked out for any other new players, so I'm curious as to whether I've missed anything. (And I don't mean iTunes for Windows.)
Re:platform irony (Score:2, Interesting)
its also great as a utility. it handles cue sheets excellently and makes encoding lossy single-file-per-song files from a lossless single-cd-file about as easy as anything. it also takes care of directory structure and tagging very well.
its an amazing program. i hate having to use winamp. fb2k handles so many audio formats (download the 'special' installer. its probably one of the best piece of software ive ever known. it has lots of support for replaygain (i dont really use
Re:platform irony (Score:2)
Good for broadband too (Score:2, Interesting)
This new format is good not only for dial-up but also for broadband corporate connections that seem to die to a crawl when people start using current streaming technologies over them.
It's good to see (Score:5, Insightful)
that folks are (again) distinguishing between the quality needed for casual use (having background noise) and sit-and-listen-to-it quality (CD/live).
One of my peeves about broadcasting over the net is that so many people want perfect signal, regardless of what they're using the broadcast for. The added bandwidth needed for studio-quality everything just means ever fatter pipes are demanded, raising the cost/price of the whole infrastructure and adding to the net congestion.
Re:It's good to see (Score:2)
Unless you're streaming mostly music, you really don't need the highest quality data transmission rate for streaming audio over the Internet. Run Real or Windows Media audio streams at 16 kbps and the sound quality is more than acceptable enough to hear mostly speech broadcasts such as news, sporting events and talk radio clearly.
I'd settle for peercast working (Score:3, Interesting)
Re:I'd settle for peercast working (Score:1)
i dont get it (Score:5, Interesting)
Re:i dont get it (Score:2)
http://www.rjamorim.com/test/32kbps/results.htm
Vorbis is simply not competitive to HE-AAC at such low bitrates.
Re:i dont get it (Score:3, Informative)
The technology has been around for a while in enterprise systems, but is only
Re:i dont get it (Score:1)
Re:i dont get it (Score:2)
If that's the case, you either have crappy hearing, crappy speakers/headphones/amp/soundcard, or some very easy to encode CD's.
SomaFM (Score:5, Informative)
Revolution? (Score:2, Insightful)
Re:Revolution? (Score:2)
>immediately undone by licensing and DRM issues.
AAC has no "licensing issues" in this context (no per broadcast fees, unlike MP3".
Neither does AAC have DRM - this is always added through nonstandard extensions. But you can do that with any format.
Re:Revolution? - Multicasting (Score:1)
Call/email your local ISP and tell them that you want SSM support. If enough people call, then they will turn it on (they already have all the equipment). Once turned on, I predict that there will be a flowering of softw
aacPlus == HE-AAC (Score:5, Informative)
There are GPL'ed implementations of HE-AAC decoders, for example at http://www.audiocoding.com, so these streams should be playable on open source systems, too.
Btw. Some of technical details in the article (notably about parametric stereo) are *complete bollocks*. What they describe is Mide-Side stereo.
Parametric stereo transmits only a mono channel plus a very small amount of sideband information that describes how to reconstruct the stereo image (via decorrelation and fading).
Re:aacPlus == HE-AAC (Score:1)
Btw. Some of technical details in the article (notably about parametric stereo) are *complete bollocks*. What they describe is Mide-Side stereo.
Parametric stereo transmits only a mono channel plus a very small amount of sideband information that describes how to reconstruct the stereo image (via decorrelation and fading).
so in other words, they transmit mono (L+R, let's call it A) plus information that can be used to reconstruct the stereo signals (L-R, let's call it B, likely to be quite small when L
Re:aacPlus == HE-AAC (Score:2)
Neither is the mono channel (necessarily) L+R.
The reconstruction isn't *anything* like you describe.
Can it get worse than mp3 (Score:3, Insightful)
AAC is indeed better.
I just wish the general public would download newer players that supported things like Vorbis, AAC.
But unfortunately,
mp3 = music file
Not "format of music file". but "music file". If it's not mp3, it's not a music file.
I think step 1 is to get rid of this carma that mp3=audio. make mp3=old audo format.
Until we do that... mp3 will be sticking around, and sucking.
Re:Can it get worse than mp3 (Score:2)
AAC is DRM'd so I avoid it like the plague anyway.
Re:Can it get worse than mp3 (Score:2)
Huh? You can add a DRM wrapper to AAC files (which is what Apple does in their iTunes Music Store). But regular AAC files (such as the ones you are getting when ripping your CDs with iTunes) are just as 'free' or 'non-free' as regular MP3 files: you can copy and play them on as many devices and computers as you want.
Re:Can it get worse than mp3 (Score:2)
Apple's music store uses a DRM'd MPEG-4 wrapper for their files, which are encoded using AAC. But that means nothing: a wrapper is quite a different thing than a codec. Look at XviD: it's a video codec which can be encapsulated in any number of wrappers (AVI, OGM, Matroska). Heck, you can even stuff an MP3 file into a wrapper and use it that way (Matroska a
Server? (Score:2)
Speaking of which, does Shoutcast or any of the other popular streaming media software packages support aacPlus?
Re:Server? (Score:2)
Good Quality down to 40kbps (Score:2)
The 48kbps stations are pretty good quality. I haven't heard a pop or crackle.
Still, now you 28.8k backwater people can at least listen to net radio that isn't awful.
Shame Apple didn't use AACPlus in the iPod Shuff
Re:Good Quality down to 40kbps (Score:2)
Now, if Apple decided to upgrade iTMS to provide AACplus files, then they'd be breaking compatibility with existing iPod models, which is probably not a wise idea, all things considered.
XMNet (Score:2)
Re:XMNet (Score:2)
Then XM sues them and they go to jail for violating the DMCA.
Next question?
Re:XMNet (Score:2)
Re:XMNet (Score:2)
We "liberate" their country through force
Re:XMNet (Score:2)
Re:XMNet (Score:1)
Multicasting Revolution (Score:1)
24K? you must not love your music! (Score:2)
New low-bitrate champ (Score:3, Interesting)
At 24kbit, Vorbis needs to encode at 16khz stereo to hit the target bitrate.
At 24kbit, AACplus can encode at 48khz stereo and still hit the target bitrate.
Doing a direct comparison, there is no competition at all. 48khz vs 16khz, aacplus wins.
While I'm very happy that such a huge leap has been made in low-bitrate audio encoding, I'm troubled as to how far Vorbis has fallen behind. They don't seem to have made any major improvements in audio quality in years.
Re:New low-bitrate champ (Score:2)
Lower bitrates, 96, 64, 32, 24, that's what is important today.
Just think, if somebody was encoding a video and had 300kbit total to work with, and they had the choice between MP3, Vorbis, or AAC+, with user support
Internet radio will always be a mug's game (Score:2)
even if you can get decent sound down at 24kbps thats still an extra 24kbps you have to add for every simultaneous listener.
podcasting's the way to go if you want to do your own audio broadcasts.
tie it in with blogtorrent and you're good to go.